Summarize Argument: Counter-Position
The author concludes that our concert series has popular appeal. This is based on the fact that our income from sales of t-shirts and other memorabilia at concerts is at least as great as that from similar sales at comparable concert series.
Identify and Describe Flaw
The author assumes that sales from t-shirts and other memorabilia is an indicator of the popularity of a concert series. The author also assumes that the comparable series mentioned in the premise have popular appeal. This overlooks the possibility that those comparable series are not popular and that the sales levels do not indicate the presence of popular appeal.
A
attacks the critics on the basis of emotional considerations rather than factual ones
The author does not cite to emotional considerations in the premise supporting the conclusion.
B
takes for granted that income from sales of memorabilia is the sole indicator of popular appeal
The author doesn’t assume that income from memorabilia sales is the “sole” indicator of popular appeal. She assumes that it is one indicator, but that doesn’t mean she thinks it’s the only one. Maybe other indicators include social media virality; this doesn’t hurt the argument.
C
takes for granted that the comparable series possess popular appeal
If this assumption were not true, then the author cannot prove that our series has popular appeal based on its similar sales to a series that isn’t popular. So, the author must take for granted that the comparable series does have popularity.
D
draws a conclusion about the popularity of a series based on a comparison with other, dissimilar events
The author cites to “comparable series.” There’s no indication that these series are dissimilar to our concert series.
E
fails to adequately distinguish the series as a whole from individual concerts in it
The argument cites to sales at “the concerts,” which refers to the concert series. Both the premise and the conclusion concern the series as a whole, not individual concerts. So the argument doesn’t need to distinguish between the series and individual concerts.
Summary
According to the stimulus, sunlight contains both UV-A and UV-B radiation. UV-A causes wrinkles, and UV-B causes sunburn. Until about 10 years ago, sunscreen blocked UV-B, but did not block UV-A.
Strongly Supported Conclusions
These facts support the inference that before 10 years ago, sunscreen did protect against sunburn, but it did not protect against wrinkles.
A
Since about ten years ago, the percentage of people who wear sunscreen every time they spend time in the sun has increased.
This is not supported. The stimulus never mentions the percentage of people who wear sunscreen, so we can’t know if it has increased or not.
B
Most people whose skin is prematurely wrinkled have spent a large amount of time in the sun without wearing sunscreen.
This is not supported. The stimulus tells us that sun exposure is one cause of premature wrinkles, but we don’t know if it’s the predominant cause. Also, until at least 10 years ago, sunscreen didn’t even make a difference to wrinkling.
C
The specific cause of premature skin wrinkling was not known until about ten years ago.
This is not supported. Just because sunscreen didn’t protect against UV-A radiation until 10 years ago, that doesn’t mean the connection between UV-A and wrinkles was unknown. Maybe it just took a long time to develop effective UV-A blocking sunscreen.
D
People who wear sunscreen now are less likely to become sunburned than were people who spent the same amount of time in the sun wearing sunscreen ten years ago.
This is not supported. Based on the stimulus, sunscreen 10 years ago did protect against the UV-B rays that cause sunburn, so there’s no reason to believe that modern sunscreen provides more protection against sunburn.
E
Until about ten years ago, people who wore sunscreen were no less likely to have premature wrinkles than were people who spent the same amount of time in the sun without wearing sunscreen.
This is strongly supported. The stimulus says that before 10 years ago, sunscreen didn’t protect against UV-A rays, which cause wrinkles. That means that wearing sunscreen could not have lowered anyone’s chance of wrinkling prematurely.
Summarize Argument: Phenomenon-Hypothesis
The author concludes that tent caterpillars engage in communal foraging. This is because tent caterpillars mark their routes to food with pheromones, and moreover mark routes to food more heavily than roots that don’t lead to food.
Notable Assumptions
The author assumes that tent caterpillars are attempting to convey information to one another by marking their trails, and that other caterpillars can pick up on such markings. If tent caterpillars don’t sense pheromones, then these trails would be useless.
A
A hungry tent caterpillar is more likely to follow heavily marked routes than lightly marked routes.
Hungry tent caterpillars know which routes to follow to food. This means tent caterpillars can indeed pick up on pheromones, and moreover know what heavily marked trails signify.
B
Tent caterpillars can detect the presence but not the concentration of pheromones.
If tent caterpillars can’t detect the concentration of pheromones, then the author’s claim about heavily marked paths is useless. This weakens the argument.
C
Sometimes individual tent caterpillars will not return to the nest until a food source is located.
This is irrelevant. The paths these tent caterpillars make would nevertheless lead to food.
D
The pheromones left by tent caterpillars are different from the pheromones left by other animals.
We don’t even know if tent caterpillars can sense pheromones.
E
The pheromones that tent caterpillars leave behind are detectable by certain other species of caterpillars.
We need to know if tent caterpillars can detect pheromones themselves. We don’t care what other caterpillars can do.
Summarize Argument
The author concludes that it is not more dangerous to swim at night than during the day in the region, even though swimmers generally swim during the day because of a fear of sharks. As support, the author says that all recent shark attacks on swimmers were during the day.
Identify and Describe Flaw
This is a percentages v. amounts flaw. While the number of shark attacks during the day is much higher than at night, we know that more people swim during the day. We can’t conclude that it’s not more dangerous to swim at night because we don’t know the rate of attacks during the day vs. at night.
As an example, if there are 50 attacks during the day and 2 attacks at night, but 10,000 people swim during the day and 10 people swim at night, it’s much more dangerous to swim at night, even though the number of night attacks is fewer.
As an example, if there are 50 attacks during the day and 2 attacks at night, but 10,000 people swim during the day and 10 people swim at night, it’s much more dangerous to swim at night, even though the number of night attacks is fewer.
A
overlooks the possibility that some sharks are primarily nocturnal hunters
The argument does overlook this possibility, but it’s not a flaw to overlook it. This is not relevant to the argument. Even if some sharks are primarily nocturnal hunters, it could be the case that most sharks hunt during the day, making it more dangerous to swim during the day.
B
bases its conclusion on evidence from an unreliable source
This is descriptively inaccurate. We have no reason to doubt the source of the information given.
C
overlooks the possibility that swimmers might feel anxiety caused by not being able to see one’s surroundings in the dark
The argument is concerned with when it’s dangerous to swim, not with the causes of swimmers’ anxiety. The conclusion is about whether it’s actually more dangerous to swim at night; swimmers’ feelings of anxiety and the causes of their anxiety is outside the scope of the argument.
D
presumes, without providing justification, that swimmers cannot be the most knowledgeable about which times of day are safest for swimming
The argument is not about swimmers’ knowledge; it’s about whether it’s more dangerous to swim at night. The argument is based on when shark attacks occur, not an assumption about what swimmers know about safety.
E
fails to take into account the possibility that the number of shark attacks at night would increase dramatically if more people swam at night
This is the flaw. Since we don’t know the rate of shark attacks during the day vs. at night, it is definitely possible that there are more attacks during the day because more people swim during the day, and if more people swam at night, there would be far more night attacks.
Denise: Crime will be reduced only when punishment is certain and is sufficiently severe to give anyone considering committing a crime reason to decide against doing so.
Reshmi: No, crime will be most effectively reduced if educational opportunities are made readily available to everyone, so that those who once viewed criminal activity as the only means of securing a comfortable lifestyle will choose a different path.
Speaker 1 Summary
Denise tells us about two requirements in order for crime to be reduced. First, punishment must be certain. And second, punishment must be severe enough to convince someone considering whether to commit a crime to decide not to do so.
Speaker 2 Summary
Reshmi asserts that crime is most effectively reduced by providing educational opportunities to everyone. This encourages criminals to choose a law-abiding life.
Objective
We’re looking for a point of agreement. They both agree that there are factors that can influence whether a person commits a crime.
A
people are capable of choosing whether or not to commit crimes
This is a point of agreement. Denise notes that people can “decide” against committing a crime. Reshmi notes that people can “choose” a different path besides committing crimes.
B
crime is the most important issue facing modern society
Neither speaker has an opinion on what is the most important issue facing modern society.
C
reducing crime requires fair and consistent responses to criminal behavior
Neither speaker has an opinion. Denise does not describe fair and consistent responses as a requirement for reducing crime. Reshmi doesn’t speak to what is required to reduce crime.
D
crimes are committed in response to economic need
Denise doesn’t have an opinion. She doesn’t suggest that crimes are or are not committed due to economic need.
E
reducing crime requires focusing on assured punishments
Reshmi doesn’t have an opinion. She doesn’t describe any requirements for reducing crime.
Summarize Argument
The author concludes that Acme Corporation offers unskilled workers excellent opportunities for advancement. The author believes this is demonstrated by the fact that Ms. Garon, the current president of the company, worked in an entry-level position requiring no special skills when she first started at the company.
Notable Assumptions
The author assumes that when Ms. Garon worked in her entry-level position, that she was an “unskilled worker.” It’s possible that even if the position did not require special skills, she still possessed skills that made her not an “unskilled worker.” The author also assumes that Ms. Garon’s advancement at the company is not a unique exception.
A
Acme’s vice president of operations also worked as an assembly line worker when he first started at Acme.
If anything, this strengthens the argument by showing that Ms. Garon’s example of advancement is not a unique exception.
B
Acme regularly hires top graduates of business schools and employs them briefly in each of a succession of entry-level positions before promoting them to management.
This raises the possibility that Ms. Garon was not an “unskilled worker.” She may have been a skilled worker temporarily placed in an entry-level position. This means she would not be a true example of an unskilled worker advancing in the company.
C
Acme promotes its own employees to senior management positions much more frequently than it hires senior managers from other companies.
This doesn’t suggest that the people being advanced might not be unskilled workers, or that Ms. Garon might not have been an unskilled worker.
D
Ms. Garon worked at Acme for more than 20 years before she was promoted to president.
The fact Ms. Garon took a long time to advance to president does not undermine the idea that the company offers unskilled workers excellent opportunities to advance. Maybe she advanced to manager, senior manager, VP, etc. over the years.
E
Acme pays entry-level employees slightly higher wages than most other businesses in the same industry.
The level of pay has no relationship to the existence of opportunities for unskilled workers to advance at the company.